The John Deere 120 deck belt part number found is GY20072. The deck belt size found is 113 in (2,870 mm) long by 0.62 in (16 mm) wide.
Deck belt part #GY20072
Deck belt sizelength 113 in (2,870 mm) and width 0.62 in (16 mm)
John Deere 120 Belt Size and Part Numbers
Mower deck belt part number
GY20072
Mower deck belt length
113 in (2,870 mm)
Mower deck belt width
0.62 in (16 mm)
Belt Size Comparison Chart
Belt length comparison
This model
113 in
Average
110 in
Low
75 in
High
155 in
Belt width comparison
This model
0.62 in
Average
0.75 in
Low
0.5 in
High
1.25 in
John Deere 120 Belt Notes
Mower deck belt note
The John Deere 120 deck belt listing shows part number GY20072, length 113 in (2,870 mm) and width 0.62 in (16 mm). Use the listed value as a buying guide, not a blind substitute for the deck-specific parts diagram
Fitment note
For the John Deere 120, use the listed specs as a buying guide, but confirm against the operator manual, parts diagram or belt label before spending money
John Deere 120 Belt Size FAQ
What should you watch when fitting a 113 in (2,870 mm) deck belt on the John Deere 120?
A 113 in (2,870 mm) deck belt leaves little room for sloppy routing. This is a longer mower belt run, so twist, idler alignment and the belt keeper positions matter. A belt can be the right length and still fail if it is routed wrong. Before blaming the new belt, compare the belt path to the routing decal and make sure it sits on the correct side of each.
Can you replace the John Deere 120 belt with the same length but different width?
The deck belt width found is 0.62 in (16 mm). That is wider than many light mower belts, so do not replace it with a thinner belt just because the length is close. It may sit too low in the pulley and slip. A belt with the wrong top width can ride too high or too low in the pulley even if the length looks right
Official information note
Mistakes do happen. Belt specs can change by year, mower deck, pulley layout, serial range and regional parts catalog. Please check the operator manual, belt routing decal, old belt label and official John Deere parts catalog before ordering a replacement belt.
